As is generally known, in beer brewing the wort must be subjected to different treatment steps. Of importance here is the wort boiling process in which the wort obtained in the lauter process is boiled and hops are then added in some form or other. The boiling of wort aims at the evaporation of excessive water for obtaining the desired wort concentration, at the destruction of enzymes and at a sterilization of the wort, at an elimination of coagulable proteins and finally at a dissolution of the hop components, above all the bitter substances in the wort.
It is also known that the wort is subsequently passed to the wort kettle in a whirlpool tank to separate the hot break. The wort is kept in a hot state in the whirlpool tank. Finally, further possible treatment steps are the introduction of the wort downstream of the wort kettle into an expansion cooler in which the wort is cooled down to about 70° C. to 75° C. In the expansion cooler DMS (dimethyl sulphide) can be expelled, for instance, with the aid of a vacuum.
In all of these treatment steps the wort is thermally treated either by letting it cool down or by heating. Normally, internal or external tube boilers are used for heating purposes, with the wort being passed therethrough. For the purpose of expansion, i.e. for expelling aromatic substances from the wort, the suggestion has already been made that the wort should be passed from below against a deflection screen so that the wort spreads in fan-like fashion inside a vessel and can thus evaporate.